plugin XEP-0176: Add non standard <tickle> element:

Add the non standard <trickle> element found with Jingle negociation with Conversations.

libervia/backend/plugins/plugin_xep_0176.py

@@ -95,7 +95,7 @@ class XEP_0176(BaseTransportHandler):
             )
         )
 
-    def build_transport(self, ice_data: dict) -> domish.Element:
+    def build_transport(self, ice_data: dict, add_trickle: bool = False) -> domish.Element:
         """Generate <transport> element from ICE data
 
         @param ice_data: a dict containing the following keys:
@@ -153,6 +153,11 @@ class XEP_0176(BaseTransportHandler):
                 candidate_elt["rel-addr"] = candidate["rel_addr"]
                 candidate_elt["rel-port"] = str(candidate["rel_port"])
 
+        if add_trickle:
+            transport_elt.addElement(
+                ("http://gultsch.de/xmpp/drafts/jingle/transports/ice-udp/option", "trickle")
+            )
+
         self.host.trigger.point("XEP-0176_build_transport", transport_elt, ice_data)
 
         return transport_elt
@@ -228,7 +233,7 @@ class XEP_0176(BaseTransportHandler):
         content_data = session["contents"][content_name]
         transport_data = content_data["transport_data"]
         ice_data = transport_data["local_ice_data"]
-        return self.build_transport(ice_data)
+        return self.build_transport(ice_data, add_trickle=True)
 
     async def _send_ice_buffer(
         self,
@@ -320,8 +325,11 @@ class XEP_0176(BaseTransportHandler):
 
         elif action == self._j.A_SESSION_INITIATE:
             # responder side, we give our candidates
-            transport_elt = self.build_transport(transport_data["local_ice_data"])
+            transport_elt = self.build_transport(
+                transport_data["local_ice_data"], add_trickle=True
+            )
         elif action == self._j.A_TRANSPORT_INFO:
+
             if session["state"] == self._j.STATE_PENDING:
                 # Session is not yet active; we buffer the arguments to replay them
                 # when the session becomes active. This makes the frontend's life easier.